The unique properties of PTFE, such as its outstanding electrical resistance, low coefficient of friction, chemical inertness, and non-support of combustion, have resulted in the use of PTFE in a wide range of applications. However, properties such as high melt viscosity and high crystallinity preclude PTFE from being processed by traditional techniques for plastics. Compounding PTFE with various materials, for example, can be difficult often resulting in substantial inhomogeneity in the final product. Moreover, the resistance of PTFE to adhere to other materials presents significant challenges in producing composite PTFE materials that do not dissociate when subjected to various environmental stresses. Currently available composite materials comprising PTFE and a carbonaceous filler, for example, can shed or leach the carbonaceous filler when subjected to various stresses.
Furthermore, the non-porous nature of PTFE produced by established methods presents additional difficulties in using this material in applications wherein porous materials are required, including diffusion, filtration, and porous barrier applications. Composite porous PTFE materials present even greater problems due to the tendency of some of these materials to dissociate into component parts when subjected to various stresses, including mechanical stresses used to induce porosity in PTFE. Additionally, the dissociative nature of some composite porous PTFE materials can render such materials unsuitable for applications where contamination resulting from the dissociation is undesirable. Composite PTFE materials having fillers, for example, may be unsuitable for filtration applications as dissociated filler can contaminate the filtered product or filtrate.